提高Mn-化矿氧降解反应效率的策略
Yin Xiong1, Yao Yang1, Xinran Feng1,2
1Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14850 , United States.
Journal of the American Chemical Society
|February 22, 2019
概括
我们开发了新型化 (MCF) 纳米晶体作为性燃料电池的有效电催化剂. 这些非贵金属催化剂具有高活性和耐久性,可用于氧化还原反应.
科学领域:
- 材料科学
- 电化学
- 能源转换
背景情况:
- 性燃料电池对于电动汽车来说是有前途的,因为它们与非贵金属催化剂的兼容性.
- 开发高效且耐用的非贵金属电催化剂用于氧降解反应 (ORR) 对于推进这一技术至关重要.
研究的目的:
- 设计和合成新型化化 (MCF) 螺旋晶体作为性介质中ORR的有效电催化剂.
- 研究三金属氧化物中Mn,Co和Fe的协同作用,以提高催化性能和耐久性.
主要方法:
- 合成Mn-化 (MCF) 螺旋晶的特定组成 (Mn0.8(CoFe2) 0.73O4).
- 催化剂在1M NaOH中的氧降解反应 (ORR) 的电化学特性.
- 现场X射线吸收光谱 (XAS) 用于在操作条件下研究氧化状态和金属-氧距离的演变.
主要成果:
- 最佳的MCF-0.8催化剂实现了0.89V的半波电位 (E1/2),与商业Pt/C非常接近.
- 经过10,000次循环,MCF- 0.8表现出极好的耐用性与最小的电位移动 (Δ E1/ 2=0. 014 V).
- 在现场XAS显示了Mn和Co之间的协同催化,Fe稳定了螺旋结构,有助于高活性和耐久性.
结论:
- 合理设计的化纳米晶体是性燃料电池中ORR的高效非贵金属电催化剂.
- ,和铁之间的协同作用是实现卓越活动和长期稳定的关键.
- 这项研究为开发用于清洁能源应用的先进电催化剂提供了机械洞察力和新策略.
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